English also has cases, we just don't think of them much. It's why pronouns are typically given as nominative/objective pairs: she/her, they/them, etc. So, similarly in German you'd probably only need to give one or two examples to make it clear which set to use. Or give all four.
Es geht nur um das Geschlecht, also er/sie/es. Mann kann das gleiche auf deutsch machen, die Fälle haben eigentlich nichts damit zu tun.
Es geht nur darum, wie sich der Person fühlt. Leute mit eine biologische "Zwischen-Zustand" sind ein gutes Beispiel für uns "0815" leute. Sollte ich sie oder er sagen zur eine Person mit weiblichen Büßen und einen Penis? Die leute (und auch andere die sich als nicht Standard fühlen) wollen einfach selber einschneiden wie man sie adressiert.
(Entschuldigung wegen meinen Grammatik-Fehlern, mein Deutsch wird ständig schlimmer)
Okay, then you use whichever English pronoun you wish to use. Again, pretty simple. I really don't think this is something you couldn't have figured out for yourself just by spending time around English speakers or even just watching English-language media or listening to English-language music.
Yep, pretty much what UNY0N said. It is about the gender, not the pronouns per se. It is an English thing that they have gendered pronouns when mostly all other stuff in the language is (assumed not) gendered. Such meticulus discussion of pronouns detached from gender makes me wonder what your reaction would be if someone held a door open for you and then called you Fraulein. Would you feel misgendered then?
Most commonly used English pronouns are typically listed as "he/him", "she/her". Sometimes people add possessive forms as well ("ie "she/her/hers". "They/them", "she/they", "he/they", "they/he", "they/she", "he/she", "any" are other common options. There's not hard rules though.
From what I recall from briefly studying German, there's still a masculine/feminine/neuter pronoun in all 4 cases. Couldn't you just use the appropriate one in each case?